1. Technical Field
The present disclosure relates to the field of electronic components, and particularly to an organic light emitting diode packaging method, a packaging structure and an organic light emitting diode device having the packaging structure.
2. Description of the Related Art
Organic light emitting diode (OLED) is a display and lighting device that is gradually being concerned in recent years, and its characteristic of flexible displaying is especially favored by people. However, OLED devices will be damaged by corrosion under the action of water vapor and oxygen, so the OLED devices currently should be protected by a packaging structure. On the other hand, for achieving flexibility of the OLED, it is required to replace conventional glass substrate by flexible substrate. Flexible substrates used currently mainly includes: ultra-thin glass, metallic foil, plastic film or the like. Plastic film is most used at present since it has characteristics including treatability and surface smoothness. However, plastic film has lower barrier property to water and oxygen, and thus a barrier layer used to obstruct water and oxygen is necessary to be added below electric circuit when plastic film is used as a flexible substrate, so as to ensure the device's ability of resisting water and oxygen. Metallic foil has a strong barrier effect but has no light transmission property, and thus encounters certain limitations when in use. Ultra-thin glass has perfect light transmission property and high barrier effect, but it is difficult to be processed.
Referring to FIG. 1, which is a schematic view showing a conventional packaging structure for an organic light emitting diode device, OLED 2 is disposed on a first substrate 1 made of plastic film, a passivation layer 3 for covering the OLED 2 is disposed on the OLED 2, and, encapsulation adhesive 4 is coated on the first substrate entirely 1 so that the passivation layer 3 is covered by the encapsulation adhesive 4. In addition, a second transparent substrate 5 is disposed on the encapsulation adhesive 4. In this structure, the OLED device adopts a bottom emission configuration, in which light is emitted from the first substrate 1 made of plastic film. However, a top emission configuration, due to its high aperture ratio and micro-cavity effect utilization, gets more attentions and is expected to be used in OLED device. In addition, although, in this configuration, the encapsulation adhesive is adopted to protect the OLED, water and oxygen will still permeate inside of the OLED packaging structure through the encapsulation adhesive, which leads to damage to the OLED.
Thereby, it is expected to achieve a flexible OLED in which use and structure of a substrate are optimized to provide an improved packaging effect so as to manufacture an OLED device with prolonged service life.